Adapter for non-circular disc

ABSTRACT

An adapter A 1  made of a synthetic resin includes an annular frame  1  having an outside diameter of 12 cm, a disk receiving section  2  provided continuously on a lower portion of an inner edge of the frame  1 , and a pair of disk pressing sections  3  and  3  provided continuously on an upper portion of the inner edge of the frame  1 . The disk receiving section  2  is provided with a circular opening  4  for causing an information recording area of a disk to face an optical reader of a disk player. A disk press-contact projection  7  formed so that a projection height is gradually increased in a disk rotation direction Y is provided on a lower surface of each disk pressing section  3 . This adapter A 1  can securely install a non-circular optical disk even if the optical disk has a slightly different size, and an installation operation of the non-circular optical disk can be easily performed.

TECHNICAL FIELD

The present invention relates to a non-circular optical disk adapterused for adapting a non-circular optical disk like an optical disk, suchas a card type CD, a business-card type CD or a DVD, to a disk loader ofa disk player included in a computer or the like.

The “disk players” herein include devices which read informationrecorded on an optical disk, devices which write information to a CD-R,a DVD-R, a DVD-RW, a DVD-RAM, a DVD+R, DVD+RW and the like, and acopying apparatus.

BACKGROUND ART

It is known in the art that the standard size of a compact disk(hereinafter, “CD”) on which information is recorded is that of a circlehaving a diameter of 12 cm or 8 cm. Recently, besides the CD of standardsize, a rectangular CD which has a length of about 85 to 89 mm and awidth of about 55 to 60 mm, and which includes a central hole and anannular information recording area provided outward of a clamping areahas appeared. The CD of this type is referred to as “a business-cardtype CD” or “a card type CD” from its size.

The business-card type CD of no regular size is difficult to beinstalled on an existing disk player without any modification. This isdue to the difficulty in positioning or centering business-card type CDsproperly for recording and reproducing within the disk player.Therefore, a business-card type CD which has a positioning projectionprovided on a lower surface of the disk, fitted into an 8 cm CD mountingconcave portion of a transport tray of a disk player, and used toperform the positioning or centering has been proposed (see WO99/0765and the like).

Nevertheless, even the business-card type CD including such apositioning means cannot be installed in the existing disk playerwithout a transport tray, particularly a slot-in or vertical diskplayer.

Japanese Patent Application Laid-Open No. 2000-11573 discloses abusiness-card type CD adapter capable of installing a business-card typeCD in such a slot-in or vertical disk player.

Meanwhile, while the standard size of the circular CD is set to have adiameter of 12 cm or 8 cm, no standard size is set at present for the CDreferred to as the business-card type CD. Therefore, as already stated,business-card type CDs of various sizes are commercially available.

The business-card type CD adapter disclosed in the Japanese PatentApplication Laid-Open No. 2000-11573 can be used for the business-cardtype CD of a specific size, and cannot be used for the business-cardtype CD of a size different from the specific size. This business-cardtype CD is made of elastic material. For this reason, if the differencein length, width, and thickness between the business-card type CD of aspecific size and that of different size is about 0.3 mm, the latter CDcan be forcedly installed in the adapter. However, this CD is likely tobe detached from the adapter within the disk player while it issubjected to a vertical or a rotational movement within the disk player.

The present invention has tackled the problems pointed out above.Therefore, it is an object of the present invention to provide anon-circular optical disk adapter capable of installing disks ofdifferent size and facilitating the disk installation operation.

Other objects of the present invention will be readily apparent from theembodiments to be described later.

SUMMARY OF THE INVENTION

In one embodiment according to the present invention a non-circularoptical disk adapter is made of an elastic material, and includes a diskreceiving section provided continuously on a lower portion of an inneredge of an annular frame having an outside diameter of 12 cm; and atleast a pair of disk pressing sections provided continuously on an upperportion of the inner edge of the annular frame, for sandwiching anon-circular optical disk between the disk pressing sections and thedisk receiving section, and is characterized in that the disk receivingsection includes a circular opening for causing an information recordingarea of the disk to face an optical reader or an optical writer includedin a disk player, and in that a disk press-contact projection orprotrusion formed so that a projection height is gradually increased ina disk rotation direction is provided on a lower surface of each of thedisk pressing sections or on an upper surface of a region of the diskreceiving section opposed to each of the disk pressing sections.

In this adapter, the non-circular optical disk mounted on the diskreceiving section is rotated so that its corners are slipped into belowthe respective disk press-contact projections, thereby positioning thecorners below the respective disk press-contact projections. Followingthe rotational operation of this disk, at least one of the disk pressingsections and the disk receiving section is gradually forced outside bythe corners of the disk, and elastically deformed, and an elasticrestoring force is accumulated therein. This accumulated restoring forceenables the corners of the disk to be securely sandwiched between thedisk press-contact projections and the disk receiving section or betweenthe disk press-contact projections and the disk pressing sections,respectively, thereby maintaining a disk installation state.

Furthermore, each disk press-contact projections is formed so that theprojection height is gradually increased in the disk rotation direction,even the disk having a peripheral edge of a different thickness or thedisk having a different length or width can be securely sandwiched.Furthermore, it is possible to prevent a defect that the state ofsandwiching the disk is released during rotation of the disk.

Examples of the non-circular optical disk installed in this adapterinclude a business-card type optical disk, a barrel optical disk, and asquare optical disk.

In the adapter, it is preferable that the disk press-contact projectionis formed so that the projection height is gradually increased in thedisk rotation direction and in a radial direction of the annular frame.

In this case, even the disk having the peripheral edge of the differentthickness or the disk having the different length or width can befurthermore securely sandwiched.

In the adapter, it is preferable that the disk press-contact projectionincludes a first disk press-contact projection formed so that theprojection height is gradually increased in the disk rotation direction,and a second disk press-contact projection adjacent to a maximumprotruding part of the first disk press-contact projection, and that aprojection height of an entire protruding surface of the second diskpress-contact projection is set to be equal to or larger than a maximumprojection height of the first disk press-contact projection.

In this case, the projection height of the entire protruding surface ofthe second disk press-contact projection is set to be equal to or largerthan the maximum projection height of the first disk press-contactprojection. Therefore, even the disk having a thin peripheral edge canbe securely sandwiched.

In the adapter, it is preferable that a disk abutment section whichprevents the disk sandwiched between the disk pressing sections and thedisk receiving section from being moved in the disk rotation directionduring rotation of the disk is provided.

In this case, a stable disk installation state is obtained. In addition,in this adapter, the disk is abutted on the abutment sections during thedisk installation operation, whereby the installation operation iscompleted. Due to this, it is possible to recognize that installation iscompleted by means other than visual recognition.

In the adapter, it is preferable that the opening is formed into acircle having a diameter of 8 cm, and provided concentrically with theannular frame.

According to this adapter, if the disk includes the positioningprojections, the disk is installed in the adapter while the diskpositioning projections are fitted into the opening. This can ensurepositioning the disk.

In the adapter, it is preferable that circular-arc elongated holes areprovided in regions of the disk receiving section opposed to therespective disk pressing sections, one or a plurality of disk pressingprojections protruding to a center of the opening are provided atpositions corresponding to the respective elongated holes on an inneredge of the disk receiving section, and that the one or plurality ofdisk pressing projections provided between positioning projections ofthe installed disk and the disk receiving section press the disk towardthe center of the opening by an elastic restoring force of thincircular-arc sections between the pressing projections and the elongatedholes.

In this case, the disk is pressed toward the center of the opening bythe elastic restoring force of the thin circular-arc sections betweenthe pressing projections and the elongated holes, thereby securelymaintaining the disk installation state.

In the adapter, it is preferable that the one or plurality of diskpressing projections are formed so that projection amounts are graduallyincreased in the disk rotation direction.

In this case, the disk is smoothly rotated during the disk installationoperation, so that the disk installation operation can be easilyperformed.

In the adapter, it is preferable that the disk receiving section isseparated from the inner edge of the annular frame right under the diskpressing sections.

In this case, an adapter formation processing can be easily performed.

In the adapter it is preferable that, in a state in which thenon-circular optical disk is installed, a total weight is set to fallwithin a range from a weight of the circular optical disk having adiameter of 8 cm to a weight of the circular optical disk having adiameter of 12 cm.

The reason is as follows: If the total weight is less than that of thecircular optical disk having a diameter of 8 cm or exceeds the weight ofthe circular optical disk having a diameter of 12 cm, a normalrotational operation cannot be attained, and for example, an unstabledisk rotational operation results. If this occurs, it will be difficultto read information recorded on the optical disk and write informationon the optical disk. It is, therefore, preferable that the total weightis set to fall within the range from the weight of the circular opticaldisk having the diameter of 8 cm to the weight of the circular opticaldisk having the diameter of 12 cm. The total weight is particularlypreferably set within the range of 3 to 22 g, more preferably set withinthe range of 5 to 18 g, most preferably set within the range of 7 to 16g.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a non-circular optical disk adapter accordingto a first embodiment of the present invention.

FIG. 2 is a bottom view of the adapter.

FIG. 3 is a cross-sectional view taken along a line A-A of FIG. 1.

FIG. 4 is a cross-sectional view taken along a line B-B of FIG. 1.

FIG. 5 is a cross-sectional view taken along a line C-C of FIG. 1.

FIG. 6 is an important part enlarged perspective view which depicts adisk press-contact projection while the adapter is placed upside down.

FIG. 7 is a plan view which depicts a state in which a business-cardtype CD is mounted on a disk receiving section of the adapter.

FIG. 8 is a plan view which depicts a state in which the business-cardtype CD is being installed in the adapter.

FIG. 9 is a plan view which depicts a state in which the business-cardtype CD is installed in the adapter.

FIG. 10 is a bottom view which depicts a state in which thebusiness-card type CD is installed in the adapter.

FIG. 11 is a cross-sectional view taken along a line D-D of FIG. 9.

FIG. 12 is a cross-sectional view taken along a line E-E of FIG. 9.

FIG. 13 is a cross-sectional view taken along a line F-F of FIG. 9.

FIG. 14 is an enlarged view of a part P shown in FIG. 10.

FIG. 15 is a plan view of the business-card type CD.

FIG. 16 is a cross-sectional view taken along a line G-G of FIG. 15.

FIG. 17 is a bottom view which depicts a state in which anotherbusiness-card type CD is installed in the adapter.

FIG. 18 is a plan view of a non-circular optical disk adapter accordingto a second embodiment of the present invention.

FIG. 19 is a plan view which depicts a state in which a barrel CD isinstalled in the adapter.

FIG. 20 is a plan view which depicts a state in which a square CD isinstalled in the adapter.

DESCRIPTION OF THE PREFFERED EMBODIMENTS

The present invention will be more particularly described by way ofexample illustrated in the drawings:

Referring to FIGS. 1 and 2, reference symbol (A1) denotes a non-circularoptical disk adapter according to a first embodiment of the presentinvention. This adapter (A1) is preferably made of an elastic syntheticresin such as ABS or polycarbonate. A business-card type CD (D1) shownin FIGS. 15 and 16 is installed, as a non-circular optical disk, in thisadapter (A1). A total weight of the adapter (that is, a sum of a weightof the business-card type CD (D1) and a weight of the adapter (A1))while this business-card type CD (D1) is installed in the adapter (A1)is set to fall within a range from a weight of a circular optical diskhaving a diameter of 8 cm to a weight of a circular optical disk havinga diameter of 12 cm both of which optical disks are commerciallyavailable. In FIG. 1, an arrow (Y) indicates a rotation direction of thebusiness-card type CD (D1) rotated by a spindle (not shown) included ina disk player.

As shown in FIGS. 15 and 16, this business-card type CD (D1) is arectangle having a length of about 85 to 89 mm and a width of 55 to 60mm, and is used for reproduction only. This business-card type CD (D1)includes a central hole (81) and an annular information recording area(83) provided outward of a clamping area (82). A positioning projection(84) extending in a circular arc fashion is formed unitarily on a lowersurface (that is, an information read surface) of this business-cardtype CD (D1).

This business-card type CD (D1) is set to have a thickness of aperipheral edge of 0.9 mm, a projection height of the positioningprojection (84) of 0.5 mm, and a total thickness of 1.4 mm.

As shown in FIGS. 1 and 2, the adapter (A1) according to the firstembodiment includes an annular frame (1), a disk receiving section (2)which receives the business-card type CD (D1), and a pair of diskpressing sections (3) and (3) for sandwiching the business-card type CD(D1) received by the disk receiving section (2) between the diskpressing sections (3) and the disk receiving section (2).

The annular frame (1) has an outside diameter of 12 cm which is equal tothe diameter of the circular CD of the standard size. A thickness ofthis annular frame (1) is set to be substantially equal to that of thecircular CD of the standard size.

The paired disk pressing sections (3) and (3) are provided continuouslyand integrally with each other above positions opposed each other on aninner edge of the annular frame (1) in an inward protruding manner. Eachdisk pressing section (3) is formed to have a size by which the diskpressing section (3) can press two adjacent corners among four cornersof the CD (D1) when the CD (D1) is installed.

The disk receiving section (2) is provided continuously and integrallyon a lower portion of the inner edge of the annular frame (1) in aninward protruding manner. A circular opening (4) having a diameter of 8cm and causing the information recording area (83) of the business-cardtype CD (D1) to face an optical reader (not shown) included in a diskplayer is provided in the central region of the disk receiving section(2), concentrically with the annular frame (1). As shown in FIGS. 3 to5, this disk receiving section (2) is separated from the inner edge ofthe annular frame (1) right under the disk pressing sections (3). Thisis due to convenience of manufacturing of the adapter (A1).

Furthermore, as shown in FIG. 1, a circular-arc elongated hole (8) isprovided in a region of this disk receiving section (2) which faces eachdisk pressing section (3). In addition, two disk pressing projections(9) protruding toward the center of the opening (4) are providedintegrally at positions corresponding to the respective elongated holes(8) on an inner edge of the disk receiving section (2). A thincircular-arc portion (10) is formed between each disk pressingprojection (9) and each elongated hole (8).

In FIG. 3, a distance between an upper surface of the disk receivingsection (2) and a lower surface of the disk pressing section (2) is setto be substantially equal to a thickness of a peripheral edge of thebusiness-card type CD (D1).

As shown in FIG. 6, a disk press-contact projection (7) composed of afirst disk press-contact projection (7 a) formed so that a projectionheight is gradually increased in a rotation direction (Y) of thebusiness-card type CD and a radial direction (X) of the annular frame(1), and a second disk press-contact projection (7 b) formed to beadjacent to a maximum protruding side of the first disk press-contactprojection (7 a) is provided on the lower surface of each disk pressingsection (3). In this disk press-contact projection (7), a projectionheight of an entire projection surface of the second disk press-contactprojection (7 b) is set equal to the projection height of the maximumprotruding part of the first disk press-contact projection (7 a).Although not shown in the drawings, the projection height of the entireprotruding surface of the second disk press-contact projection (7 b) maybe set larger than the projection height of the maximum protruding partof the first disk press-contact projection (7 a).

As shown in FIG. 6, a disk abutment section (5) is provided on a distalend side of the disk pressing section (3) in the rotation direction (Y)of the business-card type CD so as to prevent the business-card type CD(D1) sandwiched between the disk pressing sections (3) and the diskreceiving section (2) from being moved in the rotation direction (Y)during rotation of the business-card type CD by the spindle of the diskplayer. This disk abutment section (5) is formed to protrude inward fromthe inner edge of the annular frame (1), to have a lower end provided tobe continuous to the disk receiving section (2), and to have an uppersurface flush with the upper surface of the disk pressing section (3).

Subsequently, a process for installing the business-card type CD (D1) inthe adapter (A1) will be described:

First, as shown in FIG. 7, the business-card type CD (D1) is mounted onthe disk receiving section (2) so as to fit the positioning projection(84) provided on the lower surface of the CD (D1) into the opening (4).In this state, while the business-card type CD (D1) is rotatedrelatively to the adapter (A1) in the rotation direction (Y) of thebusiness-card type CD by the spindle of the disk player, a pair ofdiagonal corners (85) of the business-card type CD (D1) are slipped intobelow the respective disk pressing sections (3) as shown in FIG. 8. Whenthe card type CD (D1) is furthermore rotated in the same direction, thecorners (85) of the business-card type CD (D1) are located below therespective second disk press-contact projections (7 b) as shown in FIG.9. Following the rotational operation of the corners (85), the diskpressing sections (3) and the disk receiving section (2) are protrudedoutside and elastically deformed as shown in FIG. 13, whereby an elasticrestoring force is accumulated in the disk pressing sections (3) and thedisk receiving section (2). This elastic restoring force enables thecorners (85) of the business-card type CD (D1) to be fixedly sandwichedbetween the second disk press-contact projections (7 b) and the diskreceiving section (2), respectively, thereby maintaining an installationstate of the business-card type CD (D1). In this state in which thecorners (85) of the business-card type CD (D1) are sandwiched, thecorners (85) are abutted on the disk abutment portions (5), respectivelyas shown in FIG. 10. Due to this, the corners (85) cannot be rotated anymore, so that the installation operation of the business-card type CD iscompleted.

In this installation state of the business-card type CD, the diskpressing projections (9) are arranged between the positioningprojections (84) of the business-card type CD (D1) and the diskreceiving section (2) as shown in FIGS. 10 and 14. Thin circular-arcsections (10) formed between the disk pressing projections (9) and theelongated holes (8) of the disk receiving section (2) are slightlyforced out toward the elongated hole (8) by the disk pressingprojections (9), and are elastically deformed. An elastic restoringforce is thereby accumulated in the respective thin circular-arcportions (10). The elastic restoring force accumulated in the thincircular-arc sections (10) enable the disk pressing projections (9) topress the business-card type CD (D1) toward the center of the opening(4), thereby strongly maintaining the installation state of thebusiness-card type CD.

In this adapter (A1), as shown in FIGS. 10 and 14, the disk pressingprojections (9) are formed so that a projection amount is graduallyincreased in the rotation direction (Y) of the business-card type CD(D1). Therefore, when the business-card type CD (D1) is installed, thebusiness-card type CD (D1) can be smoothly rotated, thereby facilitatingthe installation operation of the business-card type CD. If the diskpressing projections (9) are detached from the portions between thepositioning projections (84) of the business-card type CD (D1) and thedisk receiving section (2) and deviated below the positioningprojections (84) during the installation operation of the business-cardtype CD, lower surfaces of the thin circular-arc sections (10) near thedisk pressing projections (9) are pushed by fingers as shown in FIG. 10.By doing so, the disk pressing projections (9) are forced into theportions between the positioning projections (84) of the business-cardtype CD (D1) and the disk receiving section (2), and arranged betweenthe positioning projections (84) and the disk receiving section (2).

The adapter (A1) in which the business-card type CD (D1) is thusinstalled is installed in the disk player, and the business-card type CD(D1) is rotated at a high velocity in the rotation direction of thearrow (Y) together with the adapter (A1) by the spindle included in thedisk player. At this time, even if the corners (85) of the business-cardtype CD (D1) are not located below the second disk press-contactprojections (7 b) and a force of sandwiching the corners (85) is weak,the corners (85) can be strongly sandwiched. This is because the corners(85) of the business-card type CD are moved in a direction in which theforce of sandwiching the corners (85) strongly acts on the corners (85)by the rotational operation of the business-card type CD (D1).Therefore, a defect that the business-card type CD (D1) is detached fromthe adapter (A1) does not occur.

When the business-card type CD (D1) is detached from the adapter (A1),the above installation procedures for the business-card type CD may beperformed in reverse order. Namely, the business-card type CD (D1) isrotated relatively to the adapter (A1) in an opposite direction to therotation direction (Y) of the business-card type CD. If so, the corners(85) of the business-card type CD (D1) are separated from between thesecond disk press-contact projections (7 b) and the disk receivingsection (2). By furthermore rotating the business-card type CD (D1) tothe position shown in FIG. 7, the disk (D1) is detached from the adapter(A1).

If a thickness of a peripheral edge of a business-card type CD (D1) islarger than that of the above-described business-card type CD (D1), thisbusiness-card type CD (D1) is installed in the adapter (A1) in a stateshown in FIG. 17. Namely, since the thickness of the peripheral edge ofthe business-card type CD (D1) is large, the corners (85) cannot bemoved to the positions below the second disk press-contact projections(7 b) and are located below the first disk press-contact projections (7a) even if the business-card type CD (D1) is rotated in thepredetermined rotation direction (Y). At these positions, the corners(85) of the business-card type CD (D1) are sandwiched between the firstdisk press-contact projections (7 a) and the disk receiving section (2),respectively, thereby maintaining the installation state of thebusiness-card type CD (D1). Thus, while the corners (85) of thebusiness-card type CD (D1) are sandwiched therebetween, the corners (85)are abutted on stepped portions (denoted by reference symbol 11 in FIG.6) generated between the first disk press-contact projections (7 a) andthe second disk press-contact projections (7 b). Due to this, thecorners (85) cannot be rotated any more, so that the installationoperation of the business-card type CD is completed.

According to the adapter (A1) in the first embodiment, each first diskpress-contact projections (7 a) is formed so that the projection heightis gradually increased in the rotation direction (Y) of thebusiness-card type CD (D1) and the radial direction (R) of the annularframe (1). Therefore, even if the business-card type CD (D1) is abusiness-card type CD having a peripheral edge of a different thicknessor a business-card type CD having a different length or width, thebusiness-card type CD (D1) can be securely sandwiched. Besides, sincethe projection height of the entire projection surface of the seconddisk press-contact projection (7 b) is set equal to that of the firstdisk pressing projection (7 a), even the business-card type CD (D1)having a peripheral edge of a small thickness can be securely, fixedlysandwiched.

Referring to FIGS. 18 and 19, reference symbol (A2) denotes anon-circular optical disk adapter according to a second embodiment ofthe present invention. A barrel CD (D2) is installed, as a non-circularoptical disk, into this adapter (A2). In FIGS. 18 and 19, likeconstituent elements of those of the adapter (A1) according to the firstembodiment are denoted by the same reference symbols, respectively.Configuration of the adapter (A2) according to the second embodimentwill be described mainly referring to differences in configuration fromthe adapter (A1) according to the first embodiment.

The barrel CD (D2) is a rectangle, has a pair of opposed circular-arcsides, and is used for reproduction only. For this barrel CD (D2), adiameter between the paired circular-arc sides is set at 8 cm. Thisbarrel CD (D2) does not include a positioning projection but uses thepaired circular-arc sides as positioning regions. A thickness of thisbarrel CD (D2) is set substantially equal to that of the circular CD ofthe standard size. In this adapter (A2), an annular frame (1) has anoutside diameter of 12 cm, which corresponds to the diameter of thecircular CD of the standard size, and an inside diameter of 8 cm. A diskreceiving section (2) is provided continuously and integrally on a lowerportion of an inner edge of this annular frame (1) in an inwardprotruding manner. A circular opening (4′) causing an informationrecording area of the barrel CD (D2) to face an optical reader (notshown) included in a disk player is provided in the central region ofthe disk receiving section (2), concentrically with the annular frame(1). A pair of disk pressing sections (3) and (3) are providedintegrally above opposed positions on the inner edge of the annularframe (1) in an inward protruding manner. A disk press-contactprojection (7) composed of a first disk press-contact projection (7 a)and a second disk press-contact projection (7 b) is provided on a lowersurface of each disk pressing section (3). Since the first diskpress-contact projection (7 a) and the second disk press-contactprojection (7 b) are equal in configuration to those of the adapter (A1)according to the first embodiment, they will not be repeatedly describedherein.

Procedures for installing the barrel CD (D2) in the adapter (A1), whichare equal to those for installing the business-card type CD (D2), willbe briefly described as follows. As indicated by chain lines in FIG. 18,the barrel CD (D2) is mounted on the disk receiving section (2). In thisstate, the barrel CD (D2) is rotated relatively to the adapter (A2) in arotation direction (Y) of the barrel CD by a spindle of the disk player,thereby positioning a pair of diagonal corners (85) of the barrel CD(D2) below the respective second disk press-contact projections (7 b) asshown in FIG. 19. Following the rotational operation of the corners (85)of this barrel CD (D2), the disk pressing sections (3) and the diskreceiving section (2) are forced outside by the corners (85), and areelastically deformed. An elastic restoring force is thereby accumulatedin the disk pressing sections (3) and the disk receiving section (2).This elastic restoring force enables the corners (85) of the barrel CD(D2) to be fixedly sandwiched between the second disk press-contactprojections (7 b) and the disk receiving section (2), respectively,thereby maintaining an installation state of the barrel CD (D2).

In this state in which the corners (85) of the barrel CD (D2) aresandwiched, the corners (85) are abutted on disk abutment portions (5),respectively.

Due to this, the corners (85) cannot be rotated any more, so that theinstallation operation of the barrel CD is completed. In FIG. 19, forconvenience of description, the corners (85) of the barrel CD (D2) arenot abutted on the disk abutment sections (5) but arranged at positionsslightly distant from the disk abutment sections (5).

If a thickness of a peripheral edge of the barrel CD (D2) is large, thecorners (85) of this barrel CD (D2) are located below the first diskpress-contact projections (7 a), respectively. At these positions, thecorners (85) of the barrel CD (D2) are sandwiched between the first diskpress-contact projections (7 a) and the disk receiving section (2),respectively, thereby maintaining the installation state of the barrelCD (D2).

A square CD (D3) beside the barrel CD (D2) stated above can beinstalled, as the non-circular optical disk, in the adapter (A2)according to the second embodiment as shown in FIG. 20. Since proceduresfor installing this square CD (D3) are equal to those for installing thebarrel CD (D2) stated above, repetitive procedures will not be describedherein. In FIG. 20, for convenience of description, the corners (85) ofthe square CD (D3) are not abutted on the disk abutment sections (5) butarranged to be slightly distant from the disk abutment sections (5).

The embodiments of the present invention have been described so far.However, the present invention is not limited to the embodiments butsettings can be variously changed.

For instance, according to the embodiments, the disk press-contactprojection (7) is composed of the first disk press-contact projection (7a) and the second disk press-contact projection (7 b). Alternatively,according to the present invention, the disk press-contact projection(7) may not include the second disk press-contact projection (7 b), thatis, may be composed only of the first disk press-contact projection (7a).

According to the above-stated embodiments, the disk press-contactprojections (7) are provided on the lower surface of the disk pressingsection (3). Alternatively, according to the present invention, the diskpress-contact projections (7) may be provided on an upper surface of aregion of the disk receiving section (2) opposed to the disk pressingsections (3), respectively. In this case, the corners (85) of theoptical disk are sandwiched between the disk press-contact projections(7) and the disk pressing sections (3), respectively.

Furthermore, according to the above-stated embodiments, the optical diskinstalled in the adapter is non-writable CD, that is, a reproductiononly CD (e.g., a CD-ROM or a DVD-ROM). According to the presentinvention, the optical disk may be a write-once CD (e.g., a CD-R, aDVD-R or a DVD+R) on which information can be written only once, aprogrammable CD (e.g., a CD-RW, a DVD-RW, a DVD+RW or DVD-RAM) on whichinformation can be written repeatedly, or the like. In this case, theopening (4) functions to cause the information recording area of thedisk to face the optical writer included in the disk player.

According to the above-stated embodiments, the number of pairs of diskpressing sections (3) is one but two or more pairs of disk pressingsections (3) may be used.

The adapter (A1) according to the first embodiment is intended toinstall the business-card type CD (D1), and the adapter (A2) accordingto the second embodiment is intended to install the barrel CD (D2) orthe square CD (D3). Needless to say, the adapter according to thepresent invention may install the non-circular optical disk other thanthose having the above-stated shapes.

According to the first embodiment, the adapter is constituted so thatthe annular frame (1), the disk receiving section (2), and the diskpressing sections (3) are formed unitarily. According to the presentinvention, a predetermined shape may be formed by forming theseconstituent elements independently and then bonding them.

Advantages of the present invention will be summarized as follows.

The non-circular adapter according to the present invention has thenon-circular disk mounted on the disk receiving section and rotated onlyin the predetermined direction, whereby the disk can be slipped intobelow the disk pressing sections, and the disk can be installed in theadapter with quite a simple operation.

Besides, even the disk having a peripheral portion of differentthickness or the disk having a different length or width can be steadilysecured by the sandwiching. Furthermore, it is possible to prevent thedefect that the disk sandwiching state is released and the disk isdetached within the disk player during rotation of the disk.

Furthermore, if each disk press-contact projection is formed to have apredetermined projection height, even the disk having the peripheraledge of the different thickness or the disk having the different lengthor width can be furthermore fixedly secured by the sandwiching.

If each disk press-contact projection includes the predetermined firstdisk press-contact projection and the predetermined second diskpress-contact projection, even the disk having a thin peripheral edgecan be steadily secured by the sandwiching.

If the adapter is provided with the predetermined disk abutmentsections, a stable disk installation state can be obtained. By abuttingthe disk on the disk abutment sections during the disk installationoperation, an installation completion sign can be obtained, making itpossible to recognize that installation is completed by means other thanvisual recognition.

Furthermore, if the opening is formed into a circle having a diameter of8 cm and provided concentrically with the annular frame, it is possibleto ensure positioning the non-circular optical disk having thepositioning projections.

Moreover, if the adapter includes the predetermined circular-arcelongated hole and the predetermined one or more pressing projections,the disk installation state can be securely maintained.

If the disk pressing projection is formed to have a predeterminedprojection amount, the disk can be smoothly rotated during the diskinstallation operation and the disk installation operation can be,therefore, easily performed.

If the disk receiving section is separated from the inner edge of theannular frame right under the disk pressing section, an adapterformation processing can be easily performed.

While the non-circular optical disk is installed, if the total weight isset to fall within the range from the weight of the circular opticaldisk having the diameter of 8 cm to the weight of the circular opticaldisk having the diameter of 12 cm, it is possible to ensure reading theinformation recorded on the optical disk installed in the adapter andrecording the information on the optical disk.

The present application claims priority of Japanese Patent ApplicationNo. 2002-33020 filed on Feb. 8, 2002, and a disclosed content of whichconstitutes a part of the present application.

The terms used herein and explanations therefore are used to describeseveral preferred embodiments of the present invention, and are notintended to limit the present invention. Any setting changes can beallowed as long as they are within the scope of the claims and do notdepart from the spirit of the invention.

It will be appreciated that the adapter according to the presentinvention is suited to adapt non-circular optical disks such as cardtype CDs (DVDs), business-card type CDs (DVDs), barrel CDs or square CDs(DVDs) to the disk loader of the disk player included in the computer orthe like.

It is to be understood that the invention is not limited to the exactdetails of construction, operation, exact materials, or embodimentsshown and described, as obvious modifications and equivalents will beapparent to one skilled in the art.

1. A non-circular optical disk adapter made of an elastic material,comprising: a disk receiving section provided continuously on a lowerportion of an inner edge of an annular frame having an outside diameterof 12 cm; and at least a pair of disk pressing sections providedcontinuously on an upper portion of the inner edge of the annular frame,for sandwiching a non-circular optical disk between the disk pressingsections and the disk receiving section; wherein the disk receivingsection includes a circular opening for causing an information recordingarea of the disk to face an optical reader or an optical writer includedin a disk player, and a disk press-contact projection formed so that aprojection height is gradually increased in a disk rotation direction isprovided on a lower surface of each of the disk pressing sections or onan upper surface of a region of the disk receiving section opposed toeach of the disk pressing sections.
 2. The non-circular optical diskadapter according to claim 1, wherein the disk press-contact projectionis formed so that the projection height is gradually increased in thedisk rotation direction and in a radial direction of the annular frame.3. The non-circular optical disk adapter according to claim 1, whereinthe disk press-contact projection includes a first disk press-contactprojection formed so that the projection height is gradually increasedin the disk rotation direction, and a second disk press-contactprojection adjacent to a maximum protruding part of the first diskpress-contact projection, and a projection height of an entireprotruding surface of the second disk press-contact projection is set tobe equal to or larger than a maximum projection height of the first diskpress-contact projection.
 4. The non-circular optical disk adapteraccording to claim 1, comprising a disk abutment section which preventsthe disk sandwiched between the disk pressing sections and the diskreceiving section from being moved in the disk rotation direction duringrotation of the disk.
 5. The non-circular optical disk adapter accordingto claim 1, wherein the opening is formed into a circle having adiameter of 8 cm, and provided concentrically with the annular frame. 6.The non-circular optical disk adapter according to claim 1, whereincircular-arc elongated holes are provided in regions of the diskreceiving section opposed to the respective disk pressing sections, andone or a plurality of disk pressing projections protruding to a centerof the opening are provided at positions corresponding to the respectiveelongated holes on an inner edge of the disk receiving section, and theone or plurality of disk pressing projections provided betweenpositioning projections of the installed disk and the disk receivingsection press the disk toward the center of the opening by an elasticrestoring force of thin circular-arc sections between the pressingprojections and the elongated holes.
 7. The non-circular optical diskadapter according to claim 6, wherein the one or plurality of diskpressing projections are formed so that projection amounts are graduallyincreased in the disk rotation direction.
 8. The non-circular opticaldisk adapter according to claim 1, wherein the disk receiving section isseparated from the inner edge of the annular frame right under the diskpressing sections.
 9. The non-circular optical disk adapter according toclaim 1, wherein in a state in which the non-circular optical disk isinstalled, a total weight is set to fall within a range from a weight ofthe circular optical disk having a diameter of 8 cm to a weight of thecircular optical disk having a diameter of 12 cm.
 10. A non-circularoptical disk adapter made of an elastic material, comprising: a diskreceiving section provided continuously on a portion of an inner edge ofan annular frame; and disk pressing sections for sandwiching anon-circularoptical disk between the disk pressing sections and the diskreceiving section; wherein the disk receiving section includes acircular opening for causing an information recording area of the diskto face an optical reader or an optical writer included in a diskplayer, and a disk press-contact projection formed so that a projectionheight is gradually increased in a rotation direction is provided on asurface of each of the disk pressing sections or on a surface of aregion of the disk receiving section opposed to each of the diskpressing sections.
 11. The non-circular optical disk adapter accordingto claim 10, wherein the disk press-contact projection is formed so thatthe projection height is gradually increased in the disk rotationdirection and in a radial direction of the annular frame.
 12. Thenon-circular optical disk adapter according to claim 10, wherein thedisk press-contact projection includes a first disk press-contactprojection formed so that the projection height is gradually increasedin the disk rotation direction, and a second disk press-contactprojection adjacent to a maximum protruding part of the first diskpress-contact projection, and a projection height of an entireprotruding surface of the second disk press-contact projection is set tobe equal to or larger than a maximum projection height of the first diskpress-contact projection.
 13. The non-circular optical disk adapteraccording to claim 10, comprising a disk abutment section which preventsthe disk sandwiched between the disk pressing sections and the diskreceiving section from being moved in the disk rotation direction duringrotation of the disk.
 14. The non-circular optical disk adapteraccording to claims 10, wherein the opening is formed into a circlehaving a diameter of 8 cm, and provided concentrically with the annularframe.
 15. The non-circular optical disk adapter according to claim 10,wherein circular-arc elongated holes are provided in regions of the diskreceiving section opposed to the respective disk pressing sections, andone or a plurality of disk pressing projections protruding to a centerof the opening are provided at positions corresponding to the respectiveelongated holes on an inner edge of the disk receiving section, and theone or plurality of disk pressing projections provided betweenpositioning projections of the installed disk and the disk receivingsection press the disk toward the center of the opening by an elasticrestoring force of thin circular-arc sections between the pressingprojections and the elongated holes.
 16. The non-circular optical diskadapter according to claim 15, wherein the one or plurality of diskpressing projections are formed so that projection amounts are graduallyincreased in the disk rotation direction.
 17. The non-circular opticaldisk adapter according to claim 10, wherein the disk receiving sectionis separated from the inner edge of the annular frame right under thedisk pressing sections.
 18. The non-circular optical disk adapteraccording to claim 10, wherein in a state in which the non-circularoptical disk is installed, a total weight is set to fall within a rangefrom a weight of the circular optical disk having a diameter of 8 cm toa weight of the circular optical disk having a diameter of 12 cm.